Bosques 

ver también BosquesComestibles 

Los Bosques 

de el Panfleto I de la Serie del Curso de Certificado de Diseño en Permacultura 

PUBLICADO POR  YANKEE PERMACULTURE

Se ha descubierto que los bosques son mucho más importantes de lo que esperábamos para el ciclo del oxígeno.  Pensábamos que los océanos eran los elementos más importantes. No lo son. No solo no lo son, contribuyendo  probablemente en menos del 8% de oxígeno al reciclaje atmosférico, sino que muchos están comenzando a ser  consumidores de oxígeno. Si vertimos mucho más mercurio en los mares, el océano será un consumidor de oxígeno.  El balance está cambiando. Por consiguiente, serán los bosques de los cuales dependemos a preservarnos de una  situación anárquica.    

De todos los bosques, algunos son sumamente importantes, como los bosques perennes, de los cuales hay 2 sistemas  extensivos. Uno es ecuatorial, de especies múltiples; y el otro es el tipo de los bosques fríos perennes de la tundra rusa y  los bosques perennes meridionales. Los bosques lluviosos son fundamentales para el ciclo del oxígeno y la estabilidad  atmosférica.  

Los bosques también propician gran parte las precipitaciones. Cuando se talan los bosques de las crestas, se  puede observar que la lluvia decae entre un 10 y un 30%, lo cual quizás se pueda tolerar. Lo que no se ve que sucede, es  que la precipitación puede disminuir  alrededor del 80% siendo la lluvia sólo una pequeña fracción de la precipitación total.  Es muy posible que en las tranquilas noches claras sin nubes, haya una precipitación importante sin que ninguna lluvia  sea registrada por los instrumentos en los sistemas forestales. Es particularmente cierto en los climas marítimos, pero es  factible también en todos los climas. Por lo tanto es posible producir muy rápidamente condiciones semi-desérticas  simplemente eliminando los árboles de los altos de las colinas. Esto se está haciendo a gran escala.  

Moderarlo todo es la característica de los bosques. Moderan el frío y el calor excesivos, las escorrentías  excesivas, la contaminación excesiva. Cuando los bosques se desforestan, se provocan extremos inmoderados. Y desde  luego, son los bosques quienes crean los suelos. Son uno de los muy pocos sistemas existentes para la creación de  suelos.  

¿Qué les está sucediendo a los bosques? Usamos grandes cantidades de productos del bosque de manera muy  temporal - como el papel y particularmente los periódicos.   La demanda se ha vuelto excesiva. Actualmente nos estamos excediendo en la tala por un billón de hectáreas con  respeto a las plantaciones. Pero en cualquier mes esto puede cambiar rápidamente. El último mes, por ejemplo, se  duplicó  la deforestación  de los bosques de las tierras bajas del Mississippi para la siembra de frijoles de soja.  

De todos los bosques que alguna vez hemos tenido, en Europa tan solo queda el 2%. No creo que haya ni un  árbol en Europa que exista gracias a la tolerancia del hombre o que no haya sido plantado por el mismo. No hay algo  comparable a un bosque virgen europeo. En Sudamérica queda tan solo un 8%. Y me parece que el cálculo para otras  zonas sea de un 15%. Así que hemos destruido la mayoría de los bosques y seguimos talando en un reducto bastante  pequeño.  Los ritmos de la tala varían, dependiendo de las prácticas de gestión. Pero, por lo general, hasta en los  bosques mejor gestionados, hay una pérdida constante del 4%, dando eso un margen más de unos 25 años todavía  antes que se acaben.  Y de hecho, lo que observamos por todo el Suroeste Asiático y Sudamérica, por todo el Tercer  Mundo y en dondequiera que las multinacionales puedan obtener la propiedad de los bosques en el mundo occidental, es  una perdida de casi el 100%. Es un sistema de "cortar y huir".  

Se nos ha instilado desde hace tiempo un falso sentido de seguridad, asegurándonos que las compañías de  explotación forestal están plantando 8 árboles por cada uno cortado. Lo que nos importa realmente es la biomasa.   Cuando se saca del bosque una cantidad superior a 150 toneladas, y repones algo cuyo peso no llega a los 300 gr., no se  está preservando la biomasa de ninguna manera ¿Qué usos les damos a los bosques?  La mayoría son el papel para  periódico y embalajes.  Incluso los pocos bosques que permanecen vírgenes están siendo talados para esto.  Bosques  que nunca han visto el paso del hombre, que nunca han experimentado ninguna interferencia humana, están siendo talados para el papel de periódico. Esos son los bosques en los cuales los árboles deben tener 60 m hasta la primera  rama, son como gigantescas catedrales.  Los están convirtiéndolos en astillas.  Hay árboles en Tasmania que son mucho  más altos que vuestras Secuoyas, que han sido talados y embarcados en forma de viruta.  Así que, en gran parte,  estamos degradando los bosques vírgenes al uso más bajo posible.  

Eso tiene efectos en el otro extremo del sistema.  Los residuos forestales están matando grandes áreas del mar.  La razón principal por la cual el mar Báltico, el Mediterráneo y la costa de Nueva York se han vuelto consumidores de  oxígeno es que nosotros estamos tapizando el fondo del mar con productos forestales. Aproximadamente, hay cerca de  12 billones de toneladas de dióxido de carbono que están siendo liberadas anualmente gracias a la muerte de los  bosques.  Dependemos de los bosques para capturar el dióxido de carbono.  Destruyendo los bosques, estamos  destruyendo el sistema que debería ayudarnos.  Estamos trabajando con los vestigios de lo que era del sistema.   Representa el último vestigio que hoy en día estamos desgastando. 

Los bosques vírgenes

absorben un 60% más de CO2 que los repoblados

artículo en FECYT

Los bosques naturales son más resistentes al cambio climático y pueden almacenar más carbono y durante más tiempo que las plantaciones, según un estudio.

El  emisor real es Cristovam Ricardo Cavalcanti Buarque, profesor universitario

http://www.centreofcultures.org.uk/Alien/Issue%201/Page%203%20-%20article%201%20-%20A%20world%20for%20All%20-%20O%20mundo%20para%20todos.htm

En Inglés

The Overstory Agroforestry Ejournal

http://agroforestry.net/overstory/osprev.html

Rooftop forest garden

http://www.risc.org.uk/garden/index.html

Food Forest

http://nz.youtube.com/watch?v=-5ZgzwoQ-ao&feature=related

Food in Fridges

http://nz.youtube.com/watch?v=62ge_AqaVtM&feature=related

from EcoTop

http://www.ecotop-consult.de/english/index.htm

Vital processes are very dynamic and they are subject to a permanent flow of energy, water and nutrients. In nature these processes happen all the time allowing for the development of dynamic and stable life systems. Due to their particular climate, topography and soil, humid tropical forests are home to diverse forms of flora and fauna that respond perfectly to the particularities of these regions. The regeneration, recovery and renovation of these systems, takes place through succession processes. Within these processes, each species occupies, for a certain period of time, a given space in which it contributes with its particular capacity to improve and to optimise its conditions as well as those of the members of its consortium to grow prosper and to reproduce. As time passes each species - by performing its functions- creates the necessary conditions for the development of another (more demanding) species ensuring that the energy, water and nutrient dynamics are maintained. As a result nature creates more and more complex systems which results in more diverse forms.

Initially, Ambaybo (Cecropia spp.) and Balsa wood (Ochroma pyramidale) are the main species predominant in slashed and burned (deforested) areas in alluvial sites in the Alto Beni region. As years go by, other species occupy their place until, without the intervention of man a new primary forest is re-established. By forcing nature to remain static for long periods of time (such is the case of single-crop farming), nature responds with the so-called "diseases", "pests" and "weeds". All these, however, are but mere indicators that show us that our agricultural practices are not adequate. These "diseases", "pests" and "weeds" appear when we insist on planting a single crop in the same plot over and over again, and we worsen this situation by using toxic chemicals to counterattack their effect. Instead of taking advantage of natural dynamics that result in complex systems that generate more life and fertile soils, because we do not understand them, we fight them using insecticides, herbicides, and fungicides.

By understanding and taking advantage of the principles underlying natural succession we achieve an abundant agricultural and forest production without using chemicals or struggling against "diseases" and "pests".

The principles underlying the natural succession of species were formulated and presented by Mr. Ernst Götsch during his visits to Bolivia. They have been published as the "Guía para el Establecimiento de Sistemas Agroforestales" .*

* Milz, Joachim: Guía para el Establecimiento de Sistemas Agroforestals. DED-COSUDE, La Paz-Bolivia 1998

Given this is a new approach to agro-forestry it is advisable that interventions in the plots be monitored for a certain period of time. Likewise, the whole process should be accompanied by training courses for technicians/extensionists and small farmers.

Ecotop recommends the following methodology:

• Participants are introduced to the topic.
• Identification of the parcels that will be organised (no larger than 2000m²)
• Planning the design of the parcel with small farmers and technicians.
• Small farmers and technicians organize seeds and plants to establish a plot.
• The instructor, the technicians and the small farmers establish a parcel together (during a season that guarantees adequate humidity for the germination and growth of the plants).

Organisation of a new parcel with corn, beans, hibiscus, cajanus, manioc, banana, pineapple, oranges, coffee, papaya, and all tree consortiums corresponding to the area (secondary, transition, primary) in a slash and burned parcel with little organic matter present in the soil.

The same parcel after 13 months. The species that were introduced along with the natural regeneration have created a dynamic system that covers the ground completely with vegetation and organic matter. The initial attack by the leaf cutting ants has diminished considerably.

...

•  
• Preparation of a crop plan (map) of the parcel.
• Preparation of a report and an instruction guide to follow - up on the progress of the parcel - follow - up work plan.
• After 2 - 4 months, the instructor carries out an intervention with the technicians and small farmers (selective weeding, replanting) and the first crops are harvested (corn, beans and hibiscus). The progress of the parcel is documented in written and through photographs and a follow - up work plan is prepared.

Already the first year the farmer is able to harvest self-consumption crops (corn, beans, manioc, cajanus cajan) as well as others for marketing (hibiscus, papaya, bananas, pineapples).

Twice a year the small farmers, the technicians and the instructor selectively weed the parcel. This practice is reinforced with the realisation of more in depth courses.

Note: Parcel dynamics demand a different intervention every time. At first, the intervention is aimed at removing some grasses, cyperaceous or pyperaceous, depending on the area. Afterwards, interventions are concentrate on pruning of trees, stratification and management of bananas and others, as well as trying to uniformly cover the ground with organic matter produced in the same parcel.

Cocoa

The procedure above described is the same as the one used to establish an agro-forest system whose main crop is cocoa. Corn is planted along with beans as if it were a single crop. Depending on the conditions prevalent, the farmer plants manioc, cajanus cajan, hibiscus, papaya, banana (preferably different varieties), different types of palm trees, avocado, zapote (marmalade) - tree, mango, carambola - tree and other fruits, ingas (every two meters or more), cobalt bloom (Erythrina ssp.) and other secondary species available along with long life cycle trees like the Ceiba , rubber (Hevea brasiliensis), brazil nut (Bertholletia excelsa), garlilc tree (Gallesia integrifolia) etc., depending on the species found in the ecosystem and the availability of materials.

Everything is planted at the same time and at very high densities. As the system progresses the pioneers are eliminated (corn, beans, hibiscus, cajanus cajan). Afterwards it's the papaya and the secondary species with short life cycles that are eliminated. This way the system opens-up gradually and the soil is constantly improved with the organic matter incorporated.

Young parcel with a cocoa system

The cocoa grows vigorously along with the other species. The manual work required for maintaining the parcel gradually decreases while the income from the diversified production increases constantly.

Oranges

Quiet commonly oranges are cultivated as single crops. In the best of cases, they are allowed some green cover. However, our experience has demonstrated that oranges produce more and with less problems in agro-forest systems that have been adapted to the requirements of this crop.

Orange parcel (late Valencia) with a green cover of Glycine wighiti. This parcel had serious problems with a bark beetle that caused the death of several trees.

The same plot 3 years after converting it into an agro-forest system and before the pruning and stratification of the system.

The same parcel (after the pruning and stratification works).

The soil is uniformly covered by organic matter. To stimulate flowering, the trees are pruned 2 months before flowering, leaving the plant just like that, almost fully exposed to the sun. The trees planted to occupy the high stratum are selected from those species that loose their leaves in the dry season (e.i. Ceiba, cedrillo (Spondias mombin), Ochóo (Hura crepitan)s, Tarara (Centrolobium ochroxylum).

Even during prolonged periods of drought, the fruits remain juicy and healthy. There have been more attacks by the bark beetle. After 2 - 3 years sufficient organic matter has been produced to maintain a high flow of carbon and to maintain the ground permanently covered with material originating from the pruning and the falling foliage.

Income from the banana is sufficient to cover the total maintenance costs of the plantation. During the first years pineapples can be included in the system. Two crops that adapt perfectly to the lower stratums are coffee as well as cocoa.

By Richard Black Environment correspondent, BBC News website, Barcelona

Losses are great, and continuous, says the report

The global economy is losing more money from the disappearance of forests than through the current banking crisis, according to an EU-commissioned study.

It puts the annual cost of forest loss at between $2 trillion and $5 trillion.

The figure comes from adding the value of the various services that forests perform, such as providing clean water and absorbing carbon dioxide.

The study, headed by a Deutsche Bank economist, parallels the Stern Review into the economics of climate change.

It has been discussed during many sessions here at the World Conservation Congress.

Some conservationists see it as a new way of persuading policymakers to fund nature protection rather than allowing the decline in ecosystems and species, highlighted in the release on Monday of the Red List of Threatened Species, to continue.

Capital losses

Speaking to BBC News on the fringes of the congress, study leader Pavan Sukhdev emphasised that the cost of natural decline dwarfs losses on the financial markets.

"It's not only greater but it's also continuous, it's been happening every year, year after year," he told BBC News.

Teeb will... show the risks we run by not valuing [nature] adequately." Andrew Mitchell Global Canopy Programme

"So whereas Wall Street by various calculations has to date lost, within the financial sector, $1-$1.5 trillion, the reality is that at today's rate we are losing natural capital at least between $2-$5 trillion every year."

The review that Mr Sukhdev leads, The Economics of Ecosystems and Biodiversity (Teeb), was initiated by Germany under its recent EU presidency, with the European Commission providing funding.

The first phase concluded in May when the team released its finding that forest decline could be costing about 7% of global GDP. The second phase will expand the scope to other natural systems.

Stern message

Key to understanding his conclusions is that as forests decline, nature stops providing services which it used to provide essentially for free.

So the human economy either has to provide them instead, perhaps through building reservoirs, building facilities to sequester carbon dioxide, or farming foods that were once naturally available.

Or we have to do without them; either way, there is a financial cost.

The Teeb calculations show that the cost falls disproportionately on the poor, because a greater part of their livelihood depends directly on the forest, especially in tropical regions.

The greatest cost to western nations would initially come through losing a natural absorber of the most important greenhouse gas.

Just as the Stern Review brought the economics of climate change into the political arena and helped politicians see the consequences of their policy choices, many in the conservation community believe the Teeb review will lay open the economic consequences of halting or not halting the slide in biodiversity.

"The numbers in the Stern Review enabled politicians to wake up to reality," said Andrew Mitchell, director of the Global Canopy Programme, an organisation concerned with directing financial resources into forest preservation.

"Teeb will do the same for the value of nature, and show the risks we run by not valuing it adequately."

A number of nations, businesses and global organisations are beginning to direct funds into forest conservation, and there are signs of a trade in natural ecosystems developing, analogous to the carbon trade, although it is clearly very early days.

Some have ethical concerns over the valuing of nature purely in terms of the services it provides humanity; but the counter-argument is that decades of trying to halt biodiversity decline by arguing for the intrinsic worth of nature have not worked, so something different must be tried.

Whether Mr Sukhdev's arguments will find political traction in an era of financial constraint is an open question, even though many of the governments that would presumably be called on to fund forest protection are the ones directly or indirectly paying for the review.

But, he said, governments and businesses are getting the point.

"Times have changed. Almost three years ago, even two years ago, their eyes would glaze over.

"Today, when I say this, they listen. In fact I get questions asked - so how do you calculate this, how can we monetize it, what can we do about it, why don't you speak with so and so politician or such and such business."

The aim is to complete the Teeb review by the middle of 2010, the date by which governments are committed under the Convention of Biological Diversity to have begun slowing the rate of biodiversity loss.

Richard.Black-INTERNET@bbc.co.uk